While surface mining machines are vastly larger than road milling machines, both types of machine have in common that they typically have milling drums with chisels in chisel holders. The chisels engage with a ground region and remove material form a surface of the ground region.
In the field of surface mining, quality of the mined material depends on the ratio between desired material such as material having a high ratio of mineral deposits, and undesired material such as rock.
To improve the ratio of desired material to undesired material it is desirable to determine information on a position of an interface between a material layer having the desired material and an adjacent material layer having more undesired material or other materials.
A camera may be used to provide still images or moving images of the surface area that is to be mined or that is already mined so that an operator of the surface miner can adjust the milling depth or interrupt the mining process if there is visible change in a surface composition of the ground region.
Further methods have been proposed, but all of them have drawbacks and there is a need for improvement.